This invention relates in general to the management of the supply of energy to energy consuming equipment and more particularly to an energy saving control system modifying the thermostatic control of energy supply to heating and cooling equipment for temperature regulated enclosures such as residential buildings.
The use of computer technology to control and regulate the supply of electrical energy to electrical loads in general and heating and cooling equipment in particular, is already well known. Such technology generally involves rather complex arrangements of temperature and other condition sensing inputs and timing information inputs that are processed, in accordance with stored programs to control power shedding as the overside switch on and switch off of the energy consuming loads. Also well known in the art are thermostatic controls for the gas valve coil and compressor contactor coil of heating and cooling equipment. Such thermostatic controls for residential heating and cooling equipment, for example, are necessarily compact and limited in its capability of reacting to the often conflicting factors involved in satisfying demand, accomodating equipment operating characteristics and avoiding the unnecessary expenditure of energy. While the use of the computer technology aforementioned to achieve a reduction in energy consumption without adversely affecting a satisfactory response to demand is possible, it is also obvious that extensive control system sophistication would be required including an expansion of sensor inputs at different locations and monitoring conditions other than temperature. Further, a considerable amount of installational adjustment may be required because of variables in connection with any sophisticated energy saving modification of a thermostatic building control system for heating and cooling equipment.
In connection with thermostatic control systems for heating and cooling equipment for buildings, it is already well known that the mere supply of electrical energy for operation of such equipment in response to and during closure of a thermostat switch is not satisfactory from the standpoints of comfort to the building occupants and operating efficiency. The heating or cooling capacities of such equipment necessarily exceed average demands in order to meet extreme external temperature or heat load conditions. As a result, excessive generation or absorption of heat often occurs during thermostat closure so as to create some discomfort during the open or off-time thermostat intervals. Attempts have been made to harvest the excess energy expended in such overheating or over-absorption of heat which produces temperature overshoot and discomfort. The reducing of thermostat on-time by use of programmed timers for such purposes has accordingly been proposed. However, the mere use of timing information does not take into account the many variables involved to even approach optimum results under most situations even if manual adjustment controls are provided.
It is therefore an important object of the present invention to provide an energy saving modification for a conventional type of thermostatic demand control system regulating operation of heating and cooling equipment which does not involve any expansion of condition sensing inputs or any economically prohibitive increase in costs of manufacture, installation and maintenance.
Yet another object of the invention in accordance with the foregoing object is to provide a thermostat control system for heating and cooling equipment that involves a simple manual selection of a heating or cooling operation in an energy saving mode or in the conventional mode of the thermostat control system.
Additional objects of the invention are to provide a thermostatic control system for heating and cooling equipment operationally modified by timing information to satisfy heating or cooling demands without discomfort caused by temperature overshoot or excessive heating or cooling.